The Opelousas courier., 1887-01-01
DIAMOND CUTTING.
The Art as Practised in the
Great Diamond Centre.
Various Processes Requiring Uniformity
and Nicely Of Touch.

ent who has visited the diamond quarter
of Amsterdam, Holland, says 1t j,
strange to think that the art of cutting
the diamond, though the stone itself has
been held precious from a period which
antedates history, should only have been
discovered in the sixteenth century. Be.
fore that time rough diamonds only were
used, and those were preferred which pre-
sented naturally a pyramidal figure, and
which were set with the point projecting.
In 1916 Louis de Berguem discovered the
art of cutting the stone and of polishing
it with its W dust. Then for the first
time its true beauty was revealed. It has
from time to time been cut in many
forms, as any one may see who examines
models of those most famous, but
only two are now employed
by skillful lapidarles - the rose
and the brilliant. The rose cutting is
only for thin stones. It presents on one
side a pyramid of triangular facets and
on the other a fat surface to be hidden
by the mounting. The brilliant, on the
contrary, presents on one side a fiat sur
face, surrounded by triangular facets,
and on the other a pyramid of facets, in
tended to be placed openly in the set
ting and to reflect the light. Most of
the diamond cutting and polishing es-
adjustments are in Zwanenburger STRAIT,
and unless one has q guide he finds the
locality with difficulty. Once found,
there is no trouble about seeing the
operations. The proprletors are only
too glad to receive visitors, who may be-.
come customers, for there is agood deal
of rivalry in the business. The concierge
conducts them through the place, re-
ceiving half a form (21 cents) for the
service.
The work is carried on several floors,
and the processes, though nice, are
simple, uniform and easily under
stood. The power is supplied by a
handsome steam engine in the basement
in a very simple manner By means of
cogs it is transferred to urr yht shafts
running up through the d'%S1er,nt floors.
These have great hor:= ntal puilics from
which it is conveyed to the polishing
wheels ranged along the sides of the
rooms. These are also horizontal. The
first operation consists in dividing the
diamond as many times as is deemed
necessary. Technically this is called
cleavage, and it is one of the miracles of
nature that the hardest substance known
is capable of such minute separation. 1t
is the business of the skillful
workman to tind the cleavage by
following the cams of its
crystalline forms which run parallel to
the faces of a regular octahedron. Hav-
ing found it he fixes the rough diamond
on the end of a stick, or mandrel, by
means of a cement which is easily soft
ened by heat, but hardens quickly, hold
ing the stone in its place with the
requisite tenacity. Then by the aid of
another diamond having a cutting edge
and fixed to another mandrel in the same
manner, he traces a line along the face
Of the hard crystal. It is only necessary
then to apply the edge Of a small sharp
instrument to the line he has traced,
give a smart blow and the diamond
quickly separates at the point desired.
The first cutting is done by a work
man whose hands are protected by thick
who, having fixed two diamonds
immovably in the manner just described,
them briskly together, which re-
in giving the form rose or the form
brilliant, according to the nature of the
stone or the preference of the master.
These manipulations of the diamond are
performed over little boxes, that not a
of the powder be lost. The
men engaged in it sit at a little table or
bench adjacent to the main room, whose
appurtenances are all of the most print
tive description. The polishing is per-
formed with great exactitude. The hori-
. 1ntal wheels or disks used for it are of
steel, about a foot in diameter. The
diamond dust is mixed with it before
being applied. The diamond is firmly
liked in an ~egg-shaped piece Of lead in
such a manner that only the surface
be applied to the disk is
exposed. To the lead is at
5acled a sort of stem or short handle,
which is taken by the polisher by means
q pair of pincers. When touched to
he disc the pincers are held immovable
" two pieces of iron, one of which
presses it firmly OF one side and the
'ther on the other. The polishers sit at
heir wheels in a long Eow along either
but at a little distance from 1t and
acing the middle of the room. The dia-
llonds are fixed in the leaden eggs by a
Of workmen, much less in number, /
Who sit at little furnaces along the wall. /
{ takes a keen eye to determine when
ne facet has been cut just enough and